This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A038860 #20 Jun 30 2025 16:51:43
%S A038860 215,335,485,665,875,1115,1385,1685,2015,2375,2765,3185,3635,4095,
%T A038860 4115,4625,4905,5165,5735,5805,6335,6795,6965,7625,7875,8315,9035,
%U A038860 9045,9785,10305,10565,11375,11655,12215,13085,13095,13985,14625,14915,15875
%N A038860 Numbers ending with '5' that are the difference of two positive cubes.
%C A038860 Contains (k+5(2j+1))^3-k^3 for any integers k,j>=0. - _M. F. Hasler_, May 31 2007
%F A038860 A number is in this sequence iff it is of the form (k+10j-5)^3-k^3, where k,j are any positive integers, since (k+d)^3 - k^3 = d(3(k+d/2)^2+d^2/4) == 5 (mod 10) iff d is odd and d == 0 (mod 5) (cf. A038853) - _M. F. Hasler_, Jun 07 2007
%o A038860 (PARI) A038860(Nmax=20000,a=[]) = { local(t, j5); forstep( j=1,Nmax^(1/3)/5,2, j5=5*j; for(k=1, sqrt((Nmax/j5-j5^2-3*j5)/3), if(Nmax<t=(k+j5)^3-k^3, break); a=concat(a,t))); vecsort(a) } \\ _M. F. Hasler_, Jun 07 2007
%Y A038860 Intersection of A017329 and A181123.
%K A038860 nonn,base
%O A038860 1,1
%A A038860 _Jeff Burch_
%E A038860 Corrected by _M. F. Hasler_, Jun 07 2007